Expansion cotter-pin.



P. K. STERN. BXPANS OTTER PIN.

APPLIOATIO BD 1130.3, 1912.

gm, Patented May 19, 1914,

WITNESSES as arrr o PHILIP K. STERN, OF NEW YORK, N. Y., ASSIGNOR T0 FRANK M. RAFVDALL MFG. CORPORATION, OF NEW YORK, N. Y.

EXPANSION corran-PIN.

Be it known that I, PHILIP K. STERN, a citizen of the United States,.residing in the city, county, and State of New York, have invented certain new and useful Improvements in Expansion Cotter-Pins, of which the following is a specication.

My invention in expansion cotter pins relates to a Cotter pin formed of half-round wire, bent to form an eye and shank; the latter having a cylindrical cross-section, the shank having its outer terminals cut obliquely, to form overlapping points which are bent over the oblique sides of each, to form a pointed camming end. The eye of my improved cotter pin is formed in a manner to provide a transverse oblong opening for the reception of a fiat blade, as for example, the blade of a screw driver, whereby the camming points of the shank may be brought into action to expand the same at the free end, to accomplish the locking of the pin.

The object of my invention is to provide a simple and inexpensive construction for cotter pins which will afford the security of vthe pin in its set position, ease in manipulation and application, and simpliclty in its.

construction, together with low cost of product-ion.

The feature of my invention, whereby I am enabled to attain the object thereof is characterized by the construction as depicted in the drawings hereto attached, which, when taken with the correlative appended descriptive matter form part of this specili-l cation, and the distinct features of novelty are referred to in the claims. I

lVith reference to the drawings, Figure 1 is a side elevational view of one of my improved expansion4 cotter pins in an unexpanded condition and a section of material,

as for example, a. bolt through which the pin is thrust, together with a section of a. blade, as for example, that of a screw driver, thrust into the leye of the pin in a horizontal position, in order to manipulate the same, and Fig. 2 is a similar view to that of Fig. l, illustrating the free extremity of the pin expanded by the action of the camming "'f points, being. caused to assume the position shown when the blade is forced into the inclined position, as illustrated. Fig. 3 is a similar view of the cotter pin to that of Fig. l, and a side elevational view of a fragment of the bolt shown in section in Fig. l, and,

Specification of Letters Patent.

Application 'led December 3, 1912.

Serial No. 734,757.

Fig. 4 is a view ofthe bolt similar to that of Fig. 3, taken at a position 900 from that of Fig. 3, and illustrating the camming pointsk their free ends cut olf obliquely, to provide similar projecting overlapping curved points 5 and 6. The oblique formation is referred to at 7 and 8, which is mutually engaged by the bent overpoints 5 and 6. The underside of the points 5 and G are bent to leave an oblique inner surface a on each. rlhe oblique surfaces upon which the points 5- and 6 lie provide together with the inner inclined surfaces a of the points, a pair of wedges', which will be hereinafter referred to as such, whereby, upon pulling down the point 6, by sliding the limb 1 downwardly with respect to the limb 2, illustrated in Fig. 2, by distorting the eye 3 to the right by a right-hand twlst of suitable blade or -screw driver 9, the under inclined surface a of the point 6 will slide on the wedge 7 and cause the projecting portion of the shank 4 of the pin to become distorted in two directions, namely a lateral spread leaving aA loop l0 between thelimbs l and 2, and a bulge lil opposite thereto, while at the same time, the free ends of limbs l and 2 will be displaced from their normal position, limb l being in the direction toward the observer in Figs. l and 2, and limb 2 in the opposite direction, due to the camming effect of the point 5 and the wedge 7. Thus, it will be observed that a head will be formed on-the free end of the shank 4l below the points 5 and 6. lt will beobvious that in this condition, the pin will be locked between the eye 3 and the head, resulting fr'om the loop l0 and the bulge 11.

To unlock the cotter pin, the blade 9 is rotated toward the left and brought to the position as illustrated in Fig. l when the limb l will have been slid upwardly with respect to the limb 2 and the point 6 will be elevated and brought to the position as illustrated in Fig. l to overlap the point Patented May 19, ttliit.

5, and lie above the wedge 7, whereupon, the pin may be extracted from the bolt or stud with which it is engaged. The bulge 11, in the meanwhile may be drawn through the Cotter pin holein the boltor stud. It .is obvious by distorting the eye Y3 in the opposite direction by continuing the rotation of the blade 9 to the left prior to extracting the cotter pin, the free end of the shank 4 will be again expanded by the point 5 of the limb 2 engaging the oblique surface 8 of the point 6. l

It will be understood by the above description of my improved expansion cotter pin that the same islooked by the formation of a head caused by the expansion of the shank 4 of the pin by the. sliding of the limbs l .and 2 with respect to each other, while distorting the eye 3, whereby the greatest ease in manipulation and application is aio-rded both for locking and releasing the pin and moreover that the same is of simple construction. It is obvious that the small amount of distortion required of the eye 3 in order to expand the end of the pin to form the head affords an' opportunity for making use of the pin a number of times without fracturing the-material and thus a cotter pin isl provided possessing features of durability. y

Having fully described my invention, I

vconstituting a pair of Wedges, whereby claim as new and vdesire to secure by Letters Patent ofthe United Statesl. An expansion cotter pin comprising, a pair of limbs formed of half-round wire bent intermediately of its length to form an elongated head having a transverse elongated eye, each of said limbs having an oblique free end and a curved point porticn t e outer free end of each limb will be distorted upon laterally sliding of the limbs longitudinally. Y

22. An expansion cotter pin comprising, a pair of limbs formed of half-round wire bent intermediately of its length to form a shank portionand an elongated head portion having a transverse elongated eye, each of said limbs 'having an oblique 'outer free end and a curved point having an oblique surface, whereby the outer free ends of the lim-bs will be distorted in opposite directions upon laterally sliding the limbs longitudinally, substantially ,as described.

In testimony whereof, I have signed my .name to this speciication in the presence of two subscribing Witnesses.

` PHILIP K. STERN.

Witnesses:

ELIZABETH L. STERN, ANNA MEYERS. 

